1. Field of the Invention
The present invention relates to a method for performing three-dimensional measurement to a measurement object having a predetermined shape with an optical three-dimensional measurement unit and a three-dimensional measurement apparatus to which the method is applied.
2. Description of the Related Art
In the conventional three-dimensional measurement apparatus, there is an apparatus having a function of computing many three-dimensional coordinates for a measurement object and displaying a three-dimensional image based on the computed coordinates. For example, Japanese Patent Application Laid-Open No. 2000-39566 discloses a microscope enlargement observation system provided with a microscope lens-barrel and an imaging device, in which height information on each pixel included in an imaging object domain is obtained by synthesizing plural focused focal point domains, and an image expressing a state in which three-dimensional image data formed by a pixel group to which the height information is imparted is observed from various directions is displayed.
In the system disclosed in Japanese Patent Application Laid-Open No. 2000-39566, a measurement object is a whole region included in a visual field of the imaging unit. However, frequently the region where the measurement is required is restricted in a production line or an inspection line of a plant. Because of the need for enhancing processing in in-line measurement, there is a strong demand for the three-dimensional measurement restricted to the region where the measurement is required. At the same time, for output of the measurement result, there is also a demand not only for simply supplying numerical information but also for being able to easily confirm the measurement result from the view of a user.
An object of the invention is to satisfy the above demand by displaying the image simply expressing the measurement result while the measurement result is correlated with an overall image of the measurement object even if the object region of the three-dimensional measurement in the measurement object is restricted.